Method of drawing glass cylinders.



No. 822,678. 7 PATENTLD JUNE 5,1906.

J. H. LUBBERS.

' METHOD OF DRAWING GLASS CYLINDERS.

APPLICATION 11.31) APR.12,1905.

WITNESSES to be flattened into window-glass I have disi in'der of several "mes IILNTED STATES JOHN H. Lunsnas, or

WVINDOIY GLASS MAOHIN E COMPANY,

PATENT QEFMJE;

OF PITTSBURG, ISENNSYL- VANIA, A CORPORATION OF NEW JERSEY.

METHOD OF DRAWlNG GLASS CYLENDERS- Specification of Letters Patent.

Patented June 5, 1906.

Application filed April 12,1905. Serial No 265.1 14.

To a whom it may concern.-

Be it knownthat I, John H. LUBBERS, of Allegheny, Allegheny county, Pennsylvania, have invented a new and useful Method of Drawing Glass tlylinders, of which the following is a full, clear, and exact description, reference being had to the accompanying drawing, in which the figure is a sectional side elevation showing one form of drawing apparatus which may be used for carrying out my invention.

In the drawing of glass cylinders ,or rollers,

covered that results of great importance can be secured by beginning the drawing of the cylinder proper atcomparatively low speed and then increasing this speed gradually up to the full speed at which the major portion of the cylinder is drawn. I have also discovered that I can sever the cylinder from the glass in the bath much moreeasily by largely mcreasing the speed preparatory to cutting off, thus giving thinner lass in t e lower portion to be cut off. I have also discovered that by usin the lower speed in starting the drawing oft e cylinder I can draw cylinders of a length equal to at least two or three of the cylinders or. rollers which have reviously been blown by hand. I can thus raw a cylthe length of an ordi nary roller and then sever the cylinder at an intermediate point or points to give rollers of a length desirable for flattening and workin up.

in the drawing, 2 represents the pot, conaining molten grass; 3, the furnace; 4, the lowpipe, and 5 the drawing-frame, to which the blowpipe is removably secured. The drawing-pot may be raised and lowered to admit heat to the glass or cut it on from the drawing-point, as desired.

The drawing-frame is lifted by any suit-. able connection, and I have shown-a flexible wire rope 6, which leads to a winding-drum of ordinary type, which maybe driven by a steam-engine, an electric motor, or a motor of any desirable form.

I In drawing cylinders with this form of ap' paratus the blowpipe is lowered intothe bath to cause the glass to adhere thereto, and the pipe is then drawn up, with a small a'nount of air admitted to forma neck portion 7. More air is then admitted to swell out the glass being drawn to the size of the cylinder desired, thus forming what is called the cap. During the forming of the neck and the cap and during the first part of the drawing of the cylinder proper the drawing-frame is liftedv at slow speed by suitably controlling the fluid passing to the motor or in any other desirable manner. After the cylinder proper is started the speed. of the drawing-frame is in-- creased, preferably gradually, until it reaches the full normal drawing speed, which may then be continued until the complete cylinder is drawn of the desired length. speed is then increased to a considerable extent, such as to draw a thin portion of glass at the lower end, which may be easily severed from the glass in the tank by shearing, cutting off with the flame, or otherwise. The

about as follows: If the motor gives about The . relative speedswhich I prefer to employ are r one hundred revolutions per minute in drawin the first portion, I preferably increase this to about six hundred revolutions in draw-,'

the cylinder lengtl ing the major portion of The speed at the end to thin the glass is preferably much higher, preferably about two thousand four hundred revolutions per minute. The speed which I have employed during the main drawing operation is about thirty inches per'. .minute with six hundred revolutions. After cutting off the drawingframe is lowered and the glass removed in the ordinary manner.

By this method the cylinder is made stronger and thicker in the upper part, sir as to su port a lon cylinder without breaking, and 16 change rom the slow to fast speedis preferably gradual, so as tqprevent excessive jerks, which would injure the cylinder. I am thus enabled to draw a cylinder of at least two or three times the length of an ordinary hand-blown roller, which cylinder I then crack off at an intermediate point or points and cap ofi at its ends, thus forming several lass rollers or cylinders, which are cracked ongitudinally and flattened in the or dinary manner. By thus drawing a cylinder of more thanordinary length I am enabled to increase the output and cheapen the product.

The glass cylinder may be drawn by the use of a circular bait of substantially the same size as the cylinder desired, or approximately so, without forming the neck and ca p and many other variations may be made in the form end'arrengement oi the apparatus Without departing from my invention.

l. The method-of drawing hollow gloss {LT-- ticles, consisting in starting the draw at cone pnmtively low speed continuing it such speed for aportion of the draw, and then incrossing to higher speed, and. continuing the drawing operation; scribed.

2. The method of drawing hollow glass ticles, consisting in starting the draw etcon1- paratively low speed continuing at such speed for a portion oi the draw, and then increasing to higher speed, and continuing at a, higher speed until the hollow article is drawn to the desired length; substantially as described.

3. The method of drawing hollow 9.1- ticles, consisting in starting the draw at com-- paratively low speed continuing at such speed for a portion of the draw, and the gradually increasing to higher speed, and continuing the drawing operation; substantially as described.

4. The method oiforming hollow glass articles, consisting in drawing the same "from a bath of molten glass, then materially increesing the speed to thin the. Wt lls of the article, and then severing the thinned portion; substantially described.

5. The method ol drawing hollow glass erticles, consisting in starting the draw at con1- peretively low speed, and then increasing to higher speed, continuing at such higher speed until the hollow nr'ticie is drawn to the desired length, hen increasing the speed of the substantially as do a senor/e draw to thin the glass, and severing the thin lower portion from glass oi the bath; substantially as described.

e. The'inethod of drawing hollow glass eyl; inde' s, consisting in forming aneck and cap portion, the. 1g said parts and a art of the c linder proper at comparatively" ow speed, tnen mate inlly increasing the speed, and continuing the drawing operation substantially as described. v I

7. The method of drawing hollow glass cylinders, consisting in forming a neck and cap portion, drawing said parts and 0. art of the e linder proper at comparatively low speed, then materially increasing the speed, eontin--' ning the drawing operation at hi her speed until the article is drawn. of t e desired 5 length, then further increasing the speed of the drswto tlnn the glass; and then severing the thin lower portion from the gloss of the both; substantially as described.

8. The method of drawing hollow glass cylinders which consists in starting the draw and continuing While a portion of the cylinder is formed, at a slow speed, then increasing the speed While drewii'ig the major portion of the cylinder, and finally again increasing speed to draw a thin bottom portion, the three rates of. speed being oi materially increasing character; substantially as described.

in testimony whereof I have hereunto set my hand.

JOHN H. meshes.

Witnesses J. A. BOLARD, G. D. (hznno. 

